Presentation of a digital image of an object

ABSTRACT

An example method is provided for presentation of a digital image of an object. The method comprises aligning a plurality of sensors with a projector unit, receiving, from a sensor of the plurality of sensors, an image of an object on a surface, detecting features of the object, and presenting the image on the surface based on the features of the object. The features include location and dimensions, wherein dimensions of the image match the dimensions of the object and location of the image overlap with the location of the object on the surface.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of a recently allowed U.S. patentapplication Ser. No. 15/508,373, filed on Mar. 2, 2017, which is hereinincorporated by reference in its entirety.

BACKGROUND

A capture system may be used to digitally capture images of documentsand other objects and in an effort to improve the interactive userexperience working with real objects and projected objects on a physicalwork surface. Further, a visual sensor is a sensor that can capturevisual data associated with a target. The visual data can include animage of the target or a video of the target. A cluster of heterogeneousvisual sensors (different types of visual sensors) can be used forcertain applications. Visual data collected by the heterogeneous sensorscan be combined and processed to perform a task associated with therespective application.

BRIEF DESCRIPTION OF THE DRAWINGS

For a detailed description of various examples, reference will now bemade to the accompanying drawings in which:

FIG. 1 is a schematic perspective view of an example of a computersystem in accordance with the principles disclosed herein;

FIG. 2 is another schematic perspective view of the computer system ofFIG. 1 in accordance with the principles disclosed herein;

FIG. 3 is a schematic side view of the computer system of FIG. 1 inaccordance with the principles disclosed herein;

FIG. 4 is a schematic front view of the computer system of FIG. 1 inaccordance with the principles disclosed herein;

FIG. 5 is a schematic side view of the computer system of FIG. 1 duringoperation in accordance with the principles disclosed herein;

FIG. 6 is a schematic front view of the system of FIG. 1 duringoperation in accordance with the principles disclosed herein;

FIG. 7 is a schematic side view of the computer system of FIG. 1 duringoperation in accordance with the principles disclosed herein;

FIG. 8 is a block diagram depicting a memory resource and a processingresource in accordance with the principles disclosed herein; and

FIG. 9 is a flow diagram depicting steps to implement an example.

NOTATION AND NOMENCLATURE

Certain terms are used throughout the following description and claimsto refer to particular system components. As one skilled in the art willappreciate, computer companies may refer to a component by differentnames. This document does not intend to distinguish between componentsthat differ in name but not function. In the following discussion and inthe claims, the terms “including” and “comprising” are used in anopen-ended fashion, and thus should be interpreted to mean “including,but not limited to . . . .” Also, the term “couple” or “couples” isintended to mean either an indirect or direct connection. Thus, if afirst device couples to a second device, that connection may be througha direct electrical or mechanical connection, through an indirectelectrical or mechanical connection via other devices and connections,through an optical electrical connection, or through a wirelesselectrical connection. As used herein the term “approximately” meansplus or minus 10%. In addition, as used herein, the phrase “user inputdevice” refers to any suitable device for providing an input, by a user,into an electrical system such as, for example, a mouse, keyboard, ahand (or any finger thereof), a stylus, a pointing device, etc.

DETAILED DESCRIPTION

The following discussion is directed to various examples of thedisclosure. Although one or more of these examples may be preferred, theexamples disclosed should not be interpreted, or otherwise used, aslimiting the scope of the disclosure, including the claims. In addition,one skilled in the art will understand that the following descriptionhas broad application, and the discussion of any example is meant onlyto be descriptive of that example, and not intended to intimate that thescope of the disclosure, including the claims, is limited to thatexample.

Aspects of the present disclosure described herein disclose a projectioncapture system, which includes a digital camera and a projector that arehoused together in a device. The projector functions both to illuminateobjects in the camera in a capture area for image capture and to projectand/or display digital images captured by the camera of those objectsinto a display area that overlaps the capture area. For example, aprojector projects an object's digital image in the same size (e.g.,1-to-1 ratio) as the object and in the same location as the object.Among other things, this approach allows automatic presentation of thedigital image of the object without requiring a user's manualintervention.

In one example in accordance with the present disclosure, a method forpresenting a digital image of an object is provided. The methodcomprises receiving an image of an object on a surface, detectingfeatures of the object, the features including location and dimensions,and presenting the image on the surface based on the features of theobject, wherein dimensions of the image match the dimensions of theobject, and location of the image overlap with the location of theobject on the surface.

In another example in accordance with the present disclosure, a systemis provided. The system comprises a camera to capture a digital image ofan object positioned in a location within a field of view of the camera,and a projector unit, communicatively coupled to the camera, to projectthe digital image in the location of the object, wherein size of thedigital image match size of the object.

In a further example in accordance with the present disclosure, anon-transitory computer readable medium is provided. The non-transitorycomputer-readable medium comprises instructions which, when executed,cause a device to (i) calibrate a camera with respect to a projectorunit, (ii) receive an image of an object positioned in a location withina field of view of the camera, and (iii) provide the image to bepresented in the location of the object, wherein size of the image issame as the object.

Referring now to FIGS. 1-4, a computer system 100 in accordance with theprinciples disclosed herein is shown. In this example, system 100generally comprises a support structure 110, a computing device 150, aprojector unit 180, and a touch sensitive mat 200. Computing device 150may comprise any suitable computing device while still complying withthe principles disclosed herein. For example, in some implementations,device 150 may comprise an electronic display, a smartphone, a tablet,an all-in-one computer (i.e., a display that also houses the computer'sboard), or some combination thereof. In this example, device 150 is anall-in-one computer that includes a central axis or center line 155,first or top side 150 a, a second or bottom side 150 b axially oppositethe top side 150 a, a front side 150 c extending axially between thesides 150 a, 150 b, a rear side also extending axially between the sides150 a, 150 b and generally radially opposite the front side 150 c. Adisplay 152 defines a viewing surface and is disposed along the frontside 150 c to project images for viewing and interaction by a user (notshown). In some examples, display 152 includes touch sensitivetechnology such as, for example, resistive, capacitive, acoustic wave,infrared (IR), strain gauge, optical, acoustic pulse recognition, orsome combination thereof. Therefore, throughout the followingdescription, display 152 may periodically be referred to as a touchsensitive surface or display. In addition, in some examples, device 150further includes a camera 154 that is to take images of a user while heor she is positioned in front of display 152. In some implementations,camera 154 is a web camera. Further, in some examples, device 150 alsoincludes a microphone or similar device that is arranged to receivesound inputs (e.g., voice) from a user during operation.

Referring still to FIGS. 1-4, support structure 110 includes a base 120,an upright member 140, and a top 160. Base 120 includes a first or frontend 120 a, and a second or rear end 120 b. During operation, base 120engages with a support surface 15 to support the weight of at least aportion of the components (e.g., member 140, unit 180, device 150, top160, etc.) of system 100 during operation. In this example, front end120 a of base 120 includes a raised portion 122 that is slightlyseparated above the support surface 15 thereby creating a space orclearance between portion 122 and surface 15. As will be explained inmore detail below, during operation of system 100, one side of mat 200is received within the space formed between portion 122 and surface 15to ensure proper alignment of mat 200. However, it should be appreciatedthat in other examples, other suitable alignments methods or devices maybe used while still complying with the principles disclosed herein.

Upright member 140 includes a first or upper end 140 a, a second orlower end 140 b opposite the upper end 140 a, a first or front side 140c extending between the ends 140 a, 140 b, and a second or rear side 140d opposite the front side 140 c and also extending between the ends 140a, 140 b. The lower end 140 b of member 140 is coupled to the rear end120 b of base 120, such that member 140 extends substantially upwardfrom the support surface 15.

Top 160 includes a first or proximate end 160 a, a second or distal end160 b opposite the proximate end 160 a, a top surface 160 c extendingbetween the ends 160 a, 160 b, and a bottom surface 160 d opposite thetop surface 160 c and also extending between the ends 160 a, 160 b.Proximate end 160 a of top 160 is coupled to upper end 140 a of uprightmember 140 such that distal end 160 b extends outward therefrom. As aresult, in the example shown in FIG. 2, top 160 is supported only at end160 a and thus is referred to herein as a “cantilevered” top. In someexamples, base 120, member 140, and top 160 are all monolithicallyformed; however, it should be appreciated that in other example, base120, member 140, and/or top 160 may not be monolithically formed whilestill complying with the principles disclosed herein.

Referring still to FIGS. 1-4, mat 200 includes a central axis orcenterline 205, a first or front side 200 a, and a second or rear side200 b axially opposite the front side 200 a. In this example, a touchsensitive surface 202 is disposed on mat 200 and is substantiallyaligned with the axis 205. Surface 202 may comprise any suitable touchsensitive technology for detecting and tracking one or multiple touchinputs by a user in order to allow the user to interact with softwarebeing executed by device 150 or some other computing device (not shown).For example, in some implementations, surface 202 may utilize knowntouch sensitive technologies such as, for example, resistive,capacitive, acoustic wave, infrared, strain gauge, optical, acousticpulse recognition, or some combination thereof while still complyingwith the principles disclosed herein. In addition, in this example,surface 202 extends over only a portion of mat 200; however, it shouldbe appreciated that in other examples, surface 202 may extend oversubstantially all of mat 200 while still complying with the principlesdisclosed herein.

During operation, mat 200 is aligned with base 120 of structure 110, aspreviously described to ensure proper alignment thereof. In particular,in this example, rear side 200 b of mat 200 is placed between the raisedportion 122 of base 120 and support surface 15 such that rear end 200 bis aligned with front side 120 a of base, thereby ensuring properoverall alignment of mat 200, and particularly surface 202, with othercomponents within system 100. In some examples, mat 200 is aligned withdevice 150 such that the center line 155 of device 150 is substantiallyaligned with center line 205 of mat 200; however, other alignments arepossible. In addition, as will be described in more detail below, in atleast some examples surface 202 of mat 200 and device 150 areelectrically coupled to one another such that user inputs received bysurface 202 are communicated to device 150. Any suitable wireless orwired electrical coupling or connection may be used between surface 202and device 150 such as, for example, WI-FI, BLUETOOTH®, ultrasonic,electrical cables, electrical leads, electrical spring-loaded pogo pinswith magnetic holding force, or some combination thereof, while stillcomplying with the principles disclosed herein. In this example, exposedelectrical contacts disposed on rear side 200 b of mat 200 engage withcorresponding electrical pogo-pin leads within portion 122 of base 120to transfer signals between device 150 and surface 202 during operation.In addition, in this example, the electrical contacts are held togetherby adjacent magnets located in the clearance between portion 122 of base120 and surface 15, previously described, to magnetically attract andhold (e.g., mechanically) a corresponding ferrous and/or magneticmaterial disposed along rear side 200 b of mat 200.

Referring specifically now to FIG. 3, projector unit 180 comprises anouter housing 182, and a projector assembly 184 disposed within housing182. Housing 182 includes a first or upper end 182 a, a second or lowerend 182 b opposite the upper end 182 a, and an inner cavity 183. In thisembodiment, housing 182 further includes a coupling or mounting member186 to engage with and support device 150 during operations. In generalmember 186 may be any suitable member or device for suspending andsupporting a computer device (e.g., device 150) while still complyingwith the principles disclosed herein. For example, in someimplementations, member 186 comprises hinge that includes an axis ofrotation such that a user (not shown) may rotate device 150 about theaxis of rotation to attain an optimal viewing angle therewith. Further,in some examples, device 150 is permanently or semi-permanently attachedto housing 182 of unit 180. For example, in some implementations, thehousing 180 and device 150 are integrally and/or monolithically formedas a single unit.

Thus, referring briefly to FIG. 4, when device 150 is suspended fromstructure 110 through the mounting member 186 on housing 182, projectorunit 180 (i.e., both housing 182 and assembly 184) is substantiallyhidden behind device 150 when system 100 is viewed from a viewingsurface or viewing angle that is substantially facing display 152disposed on front side 150 c of device 150. In addition, as is alsoshown in FIG. 4, when device 150 is suspended from structure 110 in themanner described, projector unit 180 (i.e., both housing 182 andassembly 184) and any image projected thereby is substantially alignedor centered with respect to the center line 155 of device 150.

Projector assembly 184 is generally disposed within cavity 183 ofhousing 182, and includes a first or upper end 184 a, a second or lowerend 184 b opposite the upper end 184 a. Upper end 184 a is proximateupper end 182 a of housing 182 while lower end 184 b is proximate lowerend 182 b of housing 182. Projector assembly 184 may comprise anysuitable digital light projector assembly for receiving data from acomputing device (e.g., device 150) and projecting an image or images(e.g., out of upper end 184 a) that correspond with that input data. Forexample, in some implementations, projector assembly 184 comprises adigital light processing (DLP) projector or a liquid crystal on silicon(LCoS) projector which are advantageously compact and power efficientprojection engines capable of multiple display resolutions and sizes,such as, for example, standard XGA (1024×768) resolution 4:3 aspectratio or standard WXGA (1280×800) resolution 16:10 aspect ratio.Projector assembly 184 is further electrically coupled to device 150 inorder to receive data therefrom for producing light and images from end184 a during operation. Projector assembly 184 may be electricallycoupled to device 150 through any suitable type of electrical couplingwhile still complying with the principles disclosed herein. For example,in some implementations, assembly 184 is electrically coupled to device150 through an electric conductor, WI-FI, BLUETOOTH®, an opticalconnection, an ultrasonic connection, or some combination thereof. Inthis example, device 150 is electrically coupled to assembly 184 throughelectrical leads or conductors (previously described) that are disposedwithin mounting member 186 such that when device 150 is suspended fromstructure 110 through member 186, the electrical leads disposed withinmember 186 contact corresponding leads or conductors disposed on device150.

Referring still to FIG. 3, top 160 further includes a fold mirror 162and a sensor bundle 164. Mirror 162 includes a highly reflective surface162 a that is disposed along bottom surface 160 d of top 160 and ispositioned to reflect images and/or light projected from upper end 184 aof projector assembly 184 toward mat 200 during operation. Mirror 162may comprise any suitable type of mirror or reflective surface whilestill complying with the principles disclosed herein. In this example,fold mirror 162 comprises a standard front surface vacuum metalizedaluminum coated glass mirror that acts to fold light emitted fromassembly 184 down to mat 200. In other examples, mirror 162 could have acomplex aspherical curvature to act as a reflective lens element toprovide additional focusing power or optical correction.

Sensor bundle 164 includes a plurality of sensors and/or cameras tomeasure and/or detect various parameters occurring on or near mat 200during operation. For example, in the specific implementation depictedin FIG. 3, bundle 164 includes an ambient light sensor 164 a, a camera(e.g., a color camera) 164 b, a depth sensor or camera 164 c, and athree dimensional (3D) user interface sensor 164 d. Each sensor may havea different resolution and field of view. In one example, each of thesesensors may be aimed at the horizontal touch sensitive mat 200 and touchsensitive surface 202 (e.g., screen for the projector). Accordingly, thefield of views of these sensors may overlap.

Examples of applications in which sensor bundle 164 can be used includeobject detection, object tracking, object recognition, objectclassification, object segmentation, object capture and reconstruction,optical touch, augmented reality presentation, or other applications.Object detection can refer to detecting presence of an object incaptured visual data, which can include an image or video. Objecttracking can refer to tracking movement of the object. Objectrecognition can refer to identifying a particular object, such asidentifying a type of the object, identifying a person, and so forth.Object classification can refer to classifying an object into one ofmultiple classes or categories. Object segmentation can refer tosegmenting an object into multiple segments. Object capture andconstruction can refer to capturing visual data of an object andconstructing a model of the object. Optical touch can refer torecognizing gestures made by a user's hand, a stylus, or other physicalartifact that are intended to provide input to a system. The gesturesare analogous to gestures corresponding to movement of a mouse device orgestures made on a touch-sensitive display panel. However, optical touchallows the gestures to be made in three-dimensional (3D) space or on aphysical target that is not configured to detect user input.

Augmented reality presentation can refer to a presentation of aphysical, real-world environment that is augmented by additionalinformation, including audio data, video data, image data, text data,and so forth. In augmented reality, the visual sensor (or a cluster ofvisual sensors) can capture visual data of a physical target. Inresponse to recognition of the captured physical target, an augmentedreality presentation can be produced. For example, the physical targetcan be a picture in a newspaper or magazine, and the capture of thepicture can cause an online electronic game to start playing. The givenpicture in the newspaper or magazine can be a game character, anadvertisement, or other information associated with the onlineelectronic game. The augmented reality presentation that is triggeredcan include the visual data of the captured physical target, as well asother data (e.g. game environment) surrounding the captured visual data.

Ambient light sensor 164 a is arranged to measure the intensity of lightof the environment surrounding system 100, in order to, in someimplementations, adjust the camera's and/or sensor's (e.g., sensors 164a, 164 b, 164 c, 164 d) exposure settings, and/or adjust the intensityof the light emitted from other sources throughout system such as, forexample, projector assembly 184, display 152, etc. Camera 164 b may, insome instances, comprise a color camera which is arranged to take eithera still image or a video of an object and/or document disposed on mat200. In one implementation, camera 164 b and projector 184 areoperatively connected to a controller for camera 164 b capturing animage of an object in mat 200 and projector 184 projecting the objectimage into mat 200 and, in some examples, for camera 164 b capturing animage of the projected object image. The controller is programmed togenerate and projector may project a user control panel, includingdevice control “buttons” such as Capture button and Undo, Fix, and OKbuttons. In another implementation, the control panel may be embedded inmat 200.

In one implementation, the object can be a two dimensional object (e.g.,a hardcopy photograph). In another implementation, the object can be athree dimensional object (e.g., a cube). The object may be placed ontomat 200, and an image of the object mat be captured by camera 164 b(and/or other cameras present in system 100). Further, a digital imageof the object may be projected onto mat 200 in the exact location of theobject, and the digital image may have the exact size of the object.Accordingly, when the object is removed to the side of mat 200, theimage projected onto mat 200 is shown provides a digital version of theobject in the exact same location (e.g., as if the object is still onmat 200).

Depth sensor 164 c generally indicates when a 3D object is on the worksurface. In particular, depth sensor 164 c may sense or detect thepresence, shape, contours, motion, and/or the 3D depth of an object (orspecific feature(s) of an object) placed on mat 200 during operation.Depth camera 164 c may be relatively robust against effects due tolighting change, presence of a shadow, or dynamic background produced bya projector. The output information from the depth sensor 164 c may bethree-dimensional (3D) depth information (also referred to as a “depthmap”), infrared (IR) image frames and red-green-blue (RGB) image frames.An “image frame” refers to a collection of visual data points that makeup an image. Depth information refers to a depth of the physical targetwith respect to the depth camera; this depth information represents thedistance between the physical target (or a portion of the physicaltarget) and the depth camera. The depth and IR sensors may be used toaid segmentation of 2D objects that appear close in RGB color (e.g.white on white) to capture mat surface 200. The 2D object may not appeardifferent than mat 200 in visual light frequencies but may havedifferent reflectivity in the IR wavelengths and thus able to assistsegmentation so long as pixels in one sensor image are known tocorrespond to pixels in the other sensor's image. If the depth sensordetects differences in the object height relative to the mat height, theanalysis of its image can aid foreground/background segmentation using atransformation of the pixels from the depth image into the RGB image.

Thus, in some implementations, sensor 164 c may employ any suitablesensor or camera arrangement to sense and detect a 3D object and/or thedepth values of each pixel (whether infrared, color, or other) disposedin the sensor's field-of-view (FOV). For example, in someimplementations sensor 164 c may comprise a single infrared (IR) camerasensor with a uniform flood of IR light, a dual IR camera sensor with auniform flood of IR light, structured light depth sensor technology,time-of-flight (TOF) depth sensor technology, or some combinationthereof. In some implementations, depth sensor 164 c may be used as areference sensor for aligning all other sensors and projector, whichwill be discussed in more detail below.

User interface sensor 164 d includes any suitable device or devices(e.g., sensor or camera) for tracking a user input device such as, forexample, a hand, stylus, pointing device, etc. In some implementations,sensor 164 d includes a pair of cameras which are arranged tostereoscopically track the location of a user input device (e.g., astylus) as it is moved by a user about the mat 200, and particularlyabout surface 202 of mat 200. In other examples, sensor 164 d may alsoor alternatively include an infrared camera(s) or sensor(s) that isarranged to detect infrared light that is either emitted or reflected bya user input device. Accordingly, the output information from sensor 164d may be 3D coordinates (i.e., x, y and z) of detected features (e.g.,finger, stylus and tool).

It should further be appreciated that bundle 164 may comprise othersensors and/or cameras either in lieu of or in addition to sensors 164a, 164 b, 164 c, 164 d, previously described. In addition, as willexplained in more detail below, each of the sensors 164 a, 164 b, 164 c,164 d within bundle 164 is electrically and communicatively coupled todevice 150 such that data generated within bundle 164 may be transmittedto device 150 and commands issued by device 150 may be communicated tothe sensors 164 a, 164 b, 164 c, 164 d during operations. As isexplained above for other components of system 100, any suitableelectrical and/or communicative coupling may be used to couple sensorbundle 164 to device 150 such as for example, an electric conductor,WI-FI, BLUETOOTH®, an optical connection, an ultrasonic connection, orsome combination thereof. In this example, electrical conductors arerouted from bundle 164, through top 160, upright member 140, andprojector unit 180 and into device 150 through the leads that aredisposed within mounting member 186, previously described.

Referring now to FIGS. 5 and 6, during operation of system 100, light187 is emitted from projector assembly 184, and reflected off of mirror162 towards mat 200 thereby displaying an image on a projector displayspace 188. In this example, space 188 is substantially rectangular andis defined by a length L₁₈₈ and a width W₁₈₈. In some examples lengthL₁₈₈ may equal approximately 16 inches, while width W₁₈₈ may equalapproximately 12 inches; however, it should be appreciated that othervalues for both length L₁₈₈ and width W₁₈₈ may be used while stillcomplying with the principles disclosed herein. In addition, the sensors(e.g., sensors 164 a, 164 b, 164 c, 164 d) within bundle 164 include asensed space 168 that, in at least some examples, overlaps and/orcorresponds with projector display space 188, previously described.Space 168 defines the area that the sensors within bundle 164 arearranged to monitor and/or detect the conditions thereof in the mannerpreviously described. In some examples, both space 188 and space 168coincide or correspond with surface 202 of mat 200, previouslydescribed, to effectively integrate the functionality of the touchsensitive surface 202, projector assembly 184, and sensor bundle 164within a defined area.

As a result, in some examples, the image projected onto surface 202 byassembly 184 serves as a second or alternative touch sensitive displaywithin system 100. In addition, interaction with the image displayed onsurface 202 is further enhanced through use of the sensors (e.g.,sensors 164 a, 164 b, 164 c, 164 d) disposed within bundle 164 asdescribed above.

Referring still to FIGS. 5-6, in addition, during operation of at leastsome examples, system 100 may capture a two dimensional (2D) image orcreate a 3D scan of a physical object such that an image of the objectmay then be projected onto the surface 202 in the same location as thephysical object and having the same size as the physical object forfurther use and manipulation thereof. In particular, in some examples,an object 40 may be placed on surface 202 such that sensors (e.g.,camera 164 b, depth sensor 164 c, etc.) within bundle 164 may detect,for instance, the location, dimensions, and in some instances, the colorof object 40, to enhance a 2D image or create a 3D scan thereof based onthe detected information. The information gathered by the sensors (e.g.,sensors 164 b, 164 c) within bundle 164 may then be routed to processorof device 150, which is described in more detail in reference to FIG.10. Thereafter, the processor directs projector assembly 184 to projectan image of object 40 onto the surface 202 in the same location asobject 40, and with the same dimensions as object 40. It should also beappreciated that in some examples, other objects such as documents orphotos may also be scanned by sensors within bundle 164 in order togenerate an image thereof which is projected onto surface 202 withassembly 184. In addition, in some examples, once an object(s) isscanned by sensors within bundle 164, the background of the image may beoptionally, digitally removed within the resulting image projected ontosurface 202 (or shown on display 152 of device 150). Thus, in someexamples, images of physical objects (e.g., object 40) may be captured,digitized, and displayed on surface 202 during operation to quickly andeasily create a digital version of a physical object to allow forfurther manipulation thereof consistent with the manner describedherein.

In other implementation, the work surface may be different than a mat(e.g., mat 200). For example, work surface may be part of the desktop orother underlying support structure. In another example, the work surfacemay be a display screen, including an LCD display. In such example,instead of projecting the image of the object, system 100 may displaythe digital image of the object on the display screen.

FIG. 7 illustrates an example of system 100 with an object on mat 200.As discussed earlier in FIGS. 1-6, system 100 includes camera 164 b forcapturing still and video images of object 40 in capture area (definedby the boundaries 189) and projector 184 for illuminating the object incapture area and for projecting images onto the object (e.g., the samephysical location as the object). For example, object 40 may be a threedimensional object (e.g., a cube) placed in capture area has beenphotographed by camera 164 b and a digital image of object 40 isprojected onto the object, where the digital image has the samedimensions as object 40. Accordingly, when object 40 is removed from thecapture area, the object image is shown projected in the same physicallocation.

In the system illustrated in FIG. 7, bundle 164 is calibrated in orderfor all the sensors to work together. In addition, sensors 164 a, 164 b,164 c, 164 d may all need to be aligned with projector unit 180 toproject the image of object 40 on top of object 40 on mat 200 and in thesame dimensions as object 40. If bundle 164 and projector unit 180 arenot properly calibrated, then combining the visual data collected by thesensors (e.g., sensors 164 a, 164 b, 164 c, 164 d) may not provideaccurate results. In accordance with some implementation, calibrationmechanisms or techniques are provided to calibrate sensors that are partof bundle 164. Such alignment provides communication between all thesecomponents. More specifically, the alignment provides propagatinginformation across different sensors and projecting information from allsensors for further processing in the various applications of system100. For the alignment to be achieved, a common coordinate system mayneed to be established. More specifically, when one sensor locates anobject (e.g., object 40) within the field of view, the other sensors andprojector unit 180 may identify the location of such object in their owncoordinate systems.

In one implementation, system 100 may include a program for verifyingalignment of the components within system 100 with respect to eachother. The program may be initiated by software executing within device150. As an example, the program may verify whether sensor bundle 164 iscalibrated properly with respect to the projector assembly 184, as willbe further described. As an example, the verification program may beexecuted regularly (e.g., once a week), at power up of system 100. Ifmisalignment of components within system 100 is detected, calibrationoperations may be performed.

As an example, alignment of the components within system 100 may beverified based according to mapping methods, such as homography. Suchmethods may involve mapping information, which is used to performcalibration among the sensors of bundle 164 in addition to calibrationwith projector assembly 184. A homography mapping is a 3D-to-2D mapping,and maps between three dimension (3D) coordinates (of the depth sensor164 c) and two dimensional (2D) coordinates (of another sensor in bundle164). For example, a 3D homography mapping may be derived for the directmapping between depth sensor 164 c and gesture sensor 164 d in sensorbundle 164. In another example, a projective mapping can be definedbetween the 3D coordinates of depth sensor 164 c and the 2D coordinatesof projector assembly 184. In particular, the 3D mapping between twosensors may include scale, rotation, translation and depth invariant.

In one example, a common coordinate system may be used based on physicalreal world coordinates based on a visible origin point that is visiblein the field of view of at least one of the plurality of sensors. Forexample, a common coordinate system that shares a perspectivetransformation with the at least one of the plurality of sensors may beidentified. This process may be re-iterated for each other pair ofvisual sensors in 164 to provide a direct 3D-to-2D mapping between eachother pair of sensors in bundle 164. As a result of the calibrationprocess (e.g., using a common coordinate system, resulting in the sameresolution and image aspect ratio across all the sensors and projector),the projected outlines match up with physical locations of object 40.

As noted above, a projective mapping can be defined between the 3Dcoordinates of depth sensor 164 c and the 2D coordinates of projectorassembly 184. Projector assembly 184 may be used to project acalibration pattern (which is a known or predefined pattern) onto theprojection surface 202. In one implementation, the calibration patternmay be projected onto a white flat surface object to make the projectedcontent visible. In some examples, the object can be a plane that is in3D space. The calibration pattern may be a checkerboard pattern. Depthsensor 164 c may capture a calibration pattern image that is projectedonto the object by projector assembly 184. The visual data (of theprojected calibration pattern image) captured by depth sensor 164 c isin a 3D space (defined by 3D coordinate), while the calibration patternprojected by projector assembly 184 is in 2D space (defined by 2Dcoordinates).

It should also be appreciated that in some examples, other objects suchas documents or photos (e.g., 2D objects) may also be scanned by sensorswithin bundle 164 in order to generate an image thereof which isprojected onto surface 202 with assembly 184. In addition, in someexamples, once an object(s) is scanned by sensors within bundle 164, thebackground of the image may be optionally, digitally removed within theresulting image projected onto surface 202 (or shown on display 152 ofdevice 150). Thus, in some examples, images of physical objects (e.g.,object 40) may be captured, digitized, and displayed on surface 202during operation to quickly and easily create a digital version of aphysical object to allow for further manipulation thereof consistentwith the manner described herein. Further, as noted earlier, thelocation of the projected image matches up with physical location ofobject 40, and the size of the projected image matches up with physicaldimensions of object 40.

Computing device 150 may include at least one processing resource. Inexamples described herein, a processing resource may include, forexample, one processor or multiple processors included in a singlecomputing device or distributed across multiple computing devices. Asused herein, a “processor” may be at least one of a central processingunit (CPU), a semiconductor-based microprocessor, a graphics processingunit (GPU), a field-programmable gate array (FPGA) to retrieve andexecute instructions, other electronic circuitry suitable for theretrieval and execution instructions stored on a machine-readablestorage medium, or a combination thereof.

As used herein, a “machine-readable storage medium” may be anyelectronic, magnetic, optical, or other physical storage apparatus tocontain or store information such as executable instructions, data, andthe like. For example, any machine-readable storage medium describedherein may be any of a storage drive (e.g., a hard drive), flash memory,Random Access Memory (RAM), any type of storage disc (e.g., a compactdisc, a DVD, etc.), and the like, or a combination thereof. Further, anymachine-readable storage medium described herein may be non-transitory.

FIG. 8 is a block diagram of an example computing device 150. In theexample of FIG. 8, computing device 150 is communicatively connected toprojector assembly 184, sensor bundle 164, and touch sensitive mat 200(as described above), and includes a processing resource 810, and amachine-readable storage medium 1020 comprising (e.g., encoded with)instructions 822, 824, and 826. In some examples, storage medium 820 mayinclude additional instructions. In other examples, instructions 822,824, 826, and any other instructions described herein in relation tostorage medium 820, may be stored on a machine-readable storage mediumremote from but accessible to computing device 150 and processingresource 810. Processing resource 810 may fetch, decode, and executeinstructions stored on storage medium 820 to implement thefunctionalities described below. In other examples, the functionalitiesof any of the instructions of storage medium 820 may be implemented inthe form of electronic circuitry, in the form of executable instructionsencoded on a machine-readable storage medium, or a combination thereof.Machine-readable storage medium 820 may be a non-transitorymachine-readable storage medium.

In the example of FIG. 8, a computing system, such as computing system100 described above in relation to FIG. 1, may comprise computing device150, projector assembly 184, sensor bundle 164, and touch sensitive mat200. In some examples, instructions 822 may include instructions forcapturing an image of an object. Instructions 824 may includeinstructions for detecting features of the object, including thelocation and dimensions, and instructions 826 may include instructionsfor projecting (and/or displaying) the image of the object in thelocation of the object and in the dimensions of the object. Moreover,the instructions 826 may include calibrating a projector with respect toa camera to, for example, identify the coordinates of such object in itsown coordinate system. The storage medium 820 may include additionalinstructions to display the image of the object based on its detectedcoordinates (e.g., physical location and dimensions) of the object.

Turning now to the operation of the system 100, FIG. 9 is a flowchart ofan example method 900 in accordance with an example implementation. Itshould be readily apparent that the processes depicted in FIG. 9represent generalized illustrations, and that other processes may beadded or the illustrated processes may be removed, modified, orrearranged in many ways. Further, it should be understood that theprocesses may represent executable instructions stored on memory thatmay cause a processing device to respond, to perform actions, to changestates, and/or to make decisions, for instance. Thus, the describedprocesses may be implemented as executable instructions and/oroperations provided by a memory associated with the computing device100.

The illustrated process 900 begins at block 910. At 910, an image of anobject is captured. In particular, this process may comprise using asensor, such as a camera to capture a digital image of a physical objectplaced on a surface in the field of view of the camera. The object maybe a 3D object, such as a cube, or it may be a 2D object, such ahardcopy of a photograph. At 920, the system detects features of theobject. In one implementation, such features may include location of theobject (e.g., coordinates) and size of the object (e.g., dimensions). Atblock 930, digital image of the object is presented based on thefeatures of the object. More specifically, the digital image of theobject is projected and/or displayed in the same location as thephysical object. Further, the size of the image of the object matchesthe size of the physical object. Accordingly, when presented, thedigital image of the object overlaps the physical object. In oneimplementation, the image may be presented through the projectorprojecting the image on a surface. In such implementation, the physicalobject is located on the surface. In another implementation, the imagemay be displayed through a display unit on a display screen. In suchimplementation, the physical object is located on the display screen.

Although the flowchart of FIG. 9 shows a specific order of performanceof certain functionalities, method 900 is not limited to that order. Forexample, the functionalities shown in succession in the flowchart may beperformed in a different order, may be executed concurrently or withpartial concurrence, or a combination thereof. In some examples,features and functionalities described herein in relation to FIG. 9 maybe provided in combination with features and functionalities describedherein in relation to any of FIGS. 1-8.

In the manner described, through use of a computer system 100 inaccordance with the principles disclosed herein, the physical object(e.g., object 40) may be scanned thereby creating a digital version ofthe physical object for viewing and/or manipulation on a display surfaceof a computing device (e.g., display 152 and/or surface 202). Further,through use of a computer system 100 in accordance with the principlesdisclosed herein, a digital shared workstation for remotely positionedusers may be created wherein physical content may be scanned, digitized,and shared among all concurrent users of the digital collaborationworkstation, and user interaction with the digital content and/orphysical objection is visible by all participants.

While device 150 has been described as an all-in-one computer, it shouldbe appreciated that in other examples, device 150 may further employ theuse of more traditional user input devices such as, for example, akeyboard and a mouse. In addition, while sensors 164 a, 164 b, 164 c,164 d within bundle 164 have been described as each representing asingle sensor or camera, it should be appreciated that each of thesensors 164 a, 164 b, 164 c, 164 d may each include multiple sensors orcameras while still complying with the principles described herein.Further, while top 160 has been described herein as a cantilevered top,it should be appreciated that in other examples, top 160 may besupported at more than one point and is thus may not be cantileveredwhile still complying with the principles disclosed herein.

The above discussion is meant to be illustrative of the principles andvarious embodiments of the present invention. Numerous variations andmodifications will become apparent to those skilled in the art once theabove disclosure is fully appreciated. It is intended that the followingclaims be interpreted to embrace all such variations and modifications.

What is claimed is:
 1. A system, comprising: a camera to capture adigital image of an object positioned in a location within a field ofview of the camera; a projector unit, communicatively coupled to thecamera, to project the digital image in the location of the object,wherein a size of the digital image matches a size of the object; aplurality of sensors that are aligned with the projector unit withrespect to a common coordinate system such that the digital image of theobject is projected; and a touch sensitive mat, wherein the object islocated on the touch sensitive mat, and the digital image is projectedon the touch sensitive mat in a same location as the object.
 2. Thesystem of claim 1, wherein the projector unit is calibrated with respectto the camera.
 3. The system of claim 1, further comprising a computingdevice to cause the camera to scan the object to produce the digitalimage and then to cause the projector unit to project the digital imageback on the object, wherein the digital image and the object overlap. 4.The system of claim 1, wherein the plurality of sensors comprise a depthdetection sensor.
 5. The system of claim 1, wherein the camera is tocapture the digital image of the object placed on a mat, and theplurality of sensors comprise a sensor to track movement of an inputobject moved across the mat, the input object comprising at least onefrom among a stylus and a user's finger.
 6. The system of claim 1,further comprising a computing device, wherein the projector unitcomprises a base and a mounting member rotatably attached to thecomputing device.
 7. The system of claim 1, further comprising anall-in-one computer communicatively coupled to the camera and theprojector unit.
 8. The system of claim 7, wherein the all-in-onecomputer stores mapping information relating to mappings between thecamera and the projector unit in a common coordinate system.
 9. Thesystem of claim 7, wherein the all-in-one computer comprises acalibration module to calibrate the projector unit with respect to thecamera.
 10. The system of claim 9, wherein the calibration module is tocalibrate the camera and the projector unit using the mappinginformation such that dimensions of an image of the object captured bythe camera and dimensions of the object are identical.
 11. A method,comprising: aligning a plurality of sensors with a projector unit withrespect to a common coordinate system; receiving, from a sensor of theplurality of sensors, an image of an object on a touch sensitive mat;detecting features of the object, the features including a location anddimensions; and presenting the image on the touch sensitive mat based onthe features of the object, wherein dimensions of the image match thedimensions of the object, and a location of the image overlaps with thelocation of the object on the touch sensitive mat.
 12. The method ofclaim 11, wherein the aligning comprises: receiving a location of theobject in a respective coordinate system of each one of the plurality ofsensors; and adjusting the respective coordinate system of each one ofthe plurality of sensors based on the location that is received toestablish a common coordinate system.
 13. The method of claim 11,wherein presenting the image on the touch sensitive mat based on thefeatures of the object comprises instructing a projector to project theimage on the touch sensitive mat based on the features of the object.14. The method of claim 11, further comprising: verifying that theplurality of sensors are aligned; and performing a calibration operationwhen the plurality of sensors are not aligned.
 15. The method of claim11, wherein presenting the image on the touch sensitive mat based on thefeatures of the object comprises instructing a display unit to displaythe image of the object based on the features of the object, wherein thetouch sensitive mat is the display screen of the display unit.
 16. Themethod of claim 11, wherein receiving the image comprises receiving theimage from a camera that captures the digital image of the object placedon a mat, and the plurality of sensors comprise a sensor to trackmovement of an input object moved across the mat, the input objectcomprising at least one from among a stylus and a user's finger.
 17. Anon-transitory machine-readable storage medium comprising instructionsexecutable by a processing resource of a computing system, theinstructions executable to: align a plurality of sensors with respect toa projector unit with respect to a common coordinate system, wherein oneof the plurality of sensors comprises a camera; receive an image of anobject positioned in a location on a touch sensitive mat within a fieldof view of the camera; and provide the image to be presented in thelocation of the object on the touch sensitive mat, wherein size of theimage is same as the object.
 18. The non-transitory machine-readablestorage medium of claim 17, further comprising instructions executableto: map coordinates of the camera to a common coordinate space shared bythe plurality of sensors; and derive a mapping between coordinates in acoordinate space of a projector that provides the image and the commoncoordinate space based on the mapped coordinates and the coordinates inthe coordinate space of the projector.
 19. The non-transitorymachine-readable storage medium of claim 18, wherein the instructions tomap coordinates comprises instructions to perform homography that mapsthree dimension coordinates to two dimension coordinates.